Most lawyers I know are ethical people; they do not lie or cheat or steal from their clients or fabricate evidence or conceal it in order to win. I'm not saying there aren't really people like that practicing law, only that in reality, they are uncommon. When they are out there, more of then than not substance abuse is involved somehow.
But lawyers are widely thought to be dishonest and untrustworthy. I think it's because most people don't have a lot of experience with lawyers to begin with, so they base their opinion on what they see on TV and in the movies.
So here's my thought: in popular media today, don't lawyers have to be a little bit sleazy in order to be interesting? Richard Gere's Billy Flynn in Chicago was interesting because he was overtly sleazy. William Shatner's Denny Crane on Boston Legal was an endearing scoundrel precisely because of his many ethical lapses. Jackie Chiles, the ambulance-chasing lawyer from Seinfeld played with elan by Phil Morris, was funny because he was such an overt parody of Johnny Cochran (a man Morris knew casually) and used obviously questionable tactics and case selection strategy.
Are characters like Atticus Finch and Perry Mason -- sincere, ethical, heartfelt crusaders for justice -- simply not interesting anymore? Matlock never interested me, so I'm not sure if he ever did anything scummy but I rather doubt it.
About the closest model of an interesting but ethical lawyer in modern popular culture I can think of is Peter Coyote's Jack McCoy from the original Law & Order series; he is interesting in no small part because he engages in a fair amount of ethical hand-wringing in the office but is able to set it aside and come out swinging after he's decided on a course of action in the courtroom. But in fact, McCoy often crosses the line -- he is not above threatening to charge people with crimes when he knows they are innocent in order to elicit testimony from them, and suppressing potentially exculpatory evidence from defense attorneys, and he has more than once been found in contempt of court for these tactics. So in fact, he winds up being an interesting character in part because he personifies the ethical challenges, and sometimes the ethical failings, of lawyers. That these are more realistic kinds of ethical failings than those facing Richard Gere in an adaptation of a Broadway musical does not, in my mind, diminish the point.
Movies and TV shows that show lawyers behaving in a morally upright fashion tend to produce either very bland and uninteresting characters, or worse yet, ones for whom the legal profession is not particularly important to their characters. Rachel Dawes (played first by Katie Hudson and then by Maggie Gyllenhall in the new Batman movies) is singularly uninteresting despite her sincerity and political savvy; she is only useful as an object of affection and does not particularly need to be a lawyer to fulfill that role. Eric McCormack's Will Truman on Will and Grace was a good guy (neurotic about his relationships) but he was interesting for being gay and his wisecracking -- again, his job as a lawyer was not really an integral or even particularly interesting part of his character. Ryan Gosling played a singularly dull prosecutor in Fracture; his "conflict" about whether to take a high-paying private firm job or continue his career as a prosecutor was not so very interesting after all.
Even Tom Cruise's Lt. Caffey in A Few Good Men was only really interesting not because he sincerely wanted to do justice, but because you watched him struggle to put aside his own demons (his ongoing intimidation by his father, his dislike of the rigidity of military life, his doubts about his clients' innocence) to start to actually do the job of a lawyer at all.
So my question is -- if it is true that a lawyer on screen must be sleazy to be interesting, is that a reason why lawyers in real life are held in so much (in my opinion, undeserved) disrepute?